If you haven't run across this site yet in your research, you may want to check it out.http://www.leosleather.com/merchant/index.htm
Leo's is a crammed little shop in Lakeview:
2841 N. Clark St
I also bought one of the leather peacoats a few years back and it was helpful to try it on before buying. The Schott jackets are quite impressive in their own right. They also have US Navy tags sewn in - I am not sure if that is an homage or if they are a real source
The shop is not what I expected, it is a tiny storefront and the inside is so crammed full of leather and wool coats that the proprietor has to retrieve the size and model you want. I haven't been in a few years, but it still looks that way when I pass it on the street.